Bond order quantifies how many electrons two atoms in a material share. But it’s a theoretical concept, not something you observe experimentally, so defining it and calculating it can get a bit fuzzy. ‘Some new chemistry students find it difficult to memorise which rules apply to which chemicals. For example, why should N2 and CF4 be described by a Lewis structure while triplet O2 and SF6are not?’ says Thomas Manz of New Mexico State University. ‘My method introduces a unifying principle where you no longer have to memorise different rules for different materials. All you have to do is calculate and you will get the accurate bond order,’ he explains.

The 2016 Journal Citation Reports® have just been released and we are pleased to announce that RSC Advances received an Impact Factor of 3.108.

We would like to thank all our authors, referees and readers who have contributed to this success, as well our Editorial and Advisory Boards for their hard work and continued support. Because of you, RSC Advances has maintained its position as a high quality, broad multidisciplinary journal.

Researchers from the UK have developed a new 3D x-ray tomography (XRT) method to visualise the effects of changing temperature on the microstructure of ice cream.

Ice cream is a mixture of milk, fats, sugars, proteins, emulsifiers, stabilisers and flavours that are aerated and then frozen to form a soft solid comprising about 30% ice, 50% air, and 5–15% fat droplets suspended in a sugar solution. Its quality depends on the size of its ice crystals and air bubbles: smaller crystals and bubbles make it smoother and creamier. And since this complex colloid is unstable above –30˚C, its microstructure will change during shipping and storage (domestic freezers are usually at around –18˚C), which will affect its taste and texture.

RSC Advances gives a warm welcome to the following new Editorial board members: Giridhar Madras, Heloise Pastore and Manuel Minas de Piedade.

Giridhar Madras has been a Full Professor in the Chemical Engineering Department at the Indian Institute of Science, India since 2007 and has published more than 450 international journal articles, which have more than 13000 citations and is among the most cited engineering scientists in India with a h-index of 55. His research interests are in the area of reaction engineering applied to polymers, supercritical fluids, and catalysis.

Heloise Pastore is currently a Full Professor at the Chemistry Institute of the State University of Campinas in Brazil and has research interests and experience in Molecular sieves, isomorphic substitution, zeolites, mcm-41 and supramolecular arrangements.

Professor Pastore is responsible for the invention of two new families of molecular sieves called CAL and UEC.

Manuel Minas da Piedade‘s research interests are mainly focused on the energetics of molecules (e.g. fullerenes, PAHs, ionic liquids), crystals (nucleation, polymorphism, crystal engineering), and, very recently, also living cells. He is currently based at the Faculty of Sciences, University of Lisbon, Portugal as an Associate Professor of Chemistry and Biochemistry.

Please see a small selection of articles from our new board members below:

Wirelessly powering small devices by harvesting energy from the environment could eliminate the need to ever recharge them. This is especially useful for embedded sensors as they will often be located in inaccessible places without a power supply, for example, on the inside of machines or the side of buildings.

Phones, tablets and other portable electronics are common, but development of equally portable power sources is lagging behind. This is a particular concern for biomedical devices such as pacemakers. Since the 1960s, researchers have made biocompatible fuel cells that generate power inside the body. However, none of these power sources has been successfully demonstrated in a human subject.

Researchers in Japan have used a machine-learning method to cut the time it takes to predict the catalytic potential of different metals.

Binding between a metal surface and an adsorbate mainly depends on the electronic structure of the metal. More energy at centre of the metal’s d-band creates a stronger bond between its surface and the adsorbate. Based on this theory, scientists have long regarded a value called the d-band centre as a key indicator of a metal’s catalytic activity.

Researchers normally compute this value independently for each metal using first-principles calculations. Now, as part of a wider interest in machine-learning applications, Ichigaku Takigawa and his group at Hokkaido University have developed a new method for predicting the d-band centre value. They use readily available data, such as density and electronegativity from other metals or bimetals, to predict the d-band centre for 11 metals and their bimetallic alloys. The results compare favourably with values obtained through density functional theory.

There is an increasing need for novel technologies to facilitate in vivo tissue visualization and drug delivery. However, this need is largely unmet due to the challenges associated with creating biocompatible materials that meet safety standards. In addition, the potential health risks associated with the accumulation of non-degradable imaging agents and drug carries represents a major obstacle in the innovation pipeline.

The intrinsic autofluorescent, biodegradable and biocompatible properties of Bovine Serum Albumin (BSA) is well appreciated. However, BSA has short excitation and emission wavelengths, which substantially restricts any in vivo biomedical applications. Motivated by a recent report suggesting that glutaraldehyde (GA)-crosslinking induces autofluorescence in protein-based nanoparticles by modifying a series of C=C and C=N bonds, a team led by Yu Lei at the Department of Biomedical Engineering, University of Connecticut, developed low-cost, non-toxic, BSA-based protein nanoparticles (average size ~40 nm) for live cell imaging and biodegradation analysis.

The nanoparticles were generated by adding drops of a prepared BSA solution to glutaraldehyde/n-butanol solution at high-speed, and the resulting product heated at 121°C to ensure sterility. Interestingly, a similar reaction carried out in the absence of the GA crosslinker did not produce autofluorescent BSA nanoparticles, suggesting that GA was indeed playing an important role in chemically transforming BSA. Using UV-visible spectroscopy, the investigators observed that BSA nanoparticles exhibited strong autofluorescence at both green (530 nm) and red (630 nm) wavelengths.

The BSA nanoparticles were not uniform in structure, owing to the random points of crosslinking within BSA, and also due to the ensuing condensation reaction that occurs during the sterilization step. Therefore, a clear mechanistic explanation for the strong autofluorescence warrants further investigation. However, the investigators speculate that GA-crosslinking and heating could result in new C=N bonds, which could synergize with the C=C bonds from tryptophan, tyrosine, phenylalanine and histidine residues with BSA, leading to enhanced green and red fluorescence.

The team went on to demonstrate the utility of the BSA nanoparticles in biomedical applications such as imaging and biodegradation. They used fluorescent microscopy techniques to visualize the entry of BSA nanoparticles into human kidney cells grown in vitro. The study also found that the BSA nanoparticles were completely degraded within 18 days of injection in mice. A mathematical model for the distribution and biodegradation of the nanoparticles was in good agreement with the experimental results. Finally, to add an additional line of evidence supporting the biocompatible nature of the BSA nanoparticles, the investigators looked for signs of tissue damage in the region surrounding the site of injection, together with an analysis of internal organs including the pancreas, liver and kidney, and report that the BSA nanoparticles are biocompatible.